title: Evaluation of a PCR method to determine the clinical significance of blood cultures with Staphylococcus epidermidis in patients with hematological malignancies.
abstract: The aim was to investigate whether the detection and quantification of Staphylococcus epidermidis DNA in blood could distinguish S. epidermidis blood stream infections (BSIs) from blood culture contaminations in patients with hematological malignancies. The hld gene was chosen to identify S. epidermidis DNA and DNA in blood samples was detected by real-time PCR. Blood samples were obtained simultaneously with blood cultures positive for S. epidermidis (n = 30), during blood culture-negative episodes (n = 10) and episodes of bacteremia with other bacteria than S. epidermidis (n = 4) and from healthy blood donors (n = 10). In addition, DNA from S. epidermidis and a selection of other bacterial species were analyzed. Three different sets of criteria were used to classify episodes with positive blood cultures with S. epidermidis as BSIs or contaminations. All DNA preparations from S. epidermidis (n = 48) were hld-positive, but other bacterial species (n = 13) were negative. Sixteen (53%) of 30 blood samples from patients with blood cultures positive for S. epidermidis were hld-positive, but none of the controls. There was no clear association between a positive hld PCR and episodes interpreted as BSIs. In conclusion, hld PCR failed to distinguish S. epidermidis BSIs from blood culture contaminations in patients with hematological malignancies.
authors.affiliation: Department of Medicine, Hematology, Örebro University Hospital, Örebro, Sweden; Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
authors.forename: Erik
authors.initials: E
authors.lastname: Ahlstrand
authors.forename: Anders
authors.initials: A
authors.lastname: Bäckman
authors.forename: Lennart
authors.initials: L
authors.lastname: Persson
authors.forename: Paula
authors.initials: P
authors.lastname: Mölling
authors.forename: Ulf
authors.initials: U
authors.lastname: Tidefelt
authors.forename: Bo
authors.initials: B
authors.lastname: Söderquist
mesh_terms: D000165:Acridine Orange; D000293:Adolescent; D000328:Adult; D000368:Aged; D016470:Bacteremia / Q000150:complications / Q000175:diagnosis / Q000382:microbiology; D001427:Bacterial Toxins / Q000235:genetics; D004269:DNA, Bacterial / Q000097:blood* / Q000235:genetics*; D005260:Female; D005798:Genes, Bacterial; D019337:Hematologic Neoplasms / Q000150:complications* / Q000382:microbiology; D006801:Humans; D008297:Male; D008875:Middle Aged; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D013203:Staphylococcal Infections / Q000150:complications* / Q000175:diagnosis / Q000382:microbiology; D013212:Staphylococcus epidermidis / Q000235:genetics* / Q000302:isolation & purification*; D055815:Young Adult
chemical_list: D001427:Bacterial Toxins; D004269:DNA, Bacterial; C025971:staphylococcal delta toxin; D000165:Acridine Orange
keywords: Coagulase-negative staphylococci; Staphylococcus epidermidis; blood culture contamination; hematological malignancy